Method And System of Molding Integral Joint

ABSTRACT

A method is provided for molding an integral joint including a stationary member and an enclosure rotatable about the stationary member. The method utilizes a joint formation assembly defining an inner cavity, a first passageway connected to the inner cavity, an outer cavity surrounding the inner cavity, and a second passageway connected to the outer cavity. The method includes the steps of: introducing moldable material into the inner cavity from the first passageway to form the stationary member; introducing moldable material into the outer cavity from the second passageway to form the enclosure; and divorcing the inner cavity from the outer cavity for separately and independently forming the enclosure around the stationary member to allow rotatable movement of the enclosure about the stationary member.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent application Ser. No. 12/305,096, which is a national phase application and claims the benefit, under 35 U.S.C. §371, of PCT/CA2007/001113, filed on Dec. 16, 2008, which in turn claims the priority of U.S. Provisional Application No. 60/815,524, filed on Jun. 20, 2006. All applications are incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The invention relates to a method and system of molding an integral joint. More particularly, the invention relates to a method of molding an integral joint including an enclosure rotatable about a stationary member.

DESCRIPTION OF RELATED ART

Molded articles are currently utilized in a wide variety of industries. Many of these molded articles include a joint or similar structure for connecting a first part to a second part. Typically, these joints have been formed with two distinct parts. First, a fixed member is molded into place. Then, a second molded member is secured to the fixed member. This two part process requires the use of fasteners or adhesives as well as secondary molding and installation operations.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a method is provided for molding an integral joint including a stationary member and an enclosure rotatable about the stationary member. The method utilizes a joint formation assembly including an inner cavity, a first passageway connected to the inner cavity, an outer cavity surrounding the inner cavity, and a second passageway connected to the outer cavity. The method includes the steps of: introducing moldable material into the inner cavity from the first passageway to form the stationary member; introducing moldable material into the outer cavity from the second passageway to form the enclosure; and divorcing the inner cavity from the outer cavity for separately and independently forming the enclosure around the stationary member to allow rotatable movement of the enclosure about the stationary member.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a perspective view of a molded, integral joint for connecting first and second parts;

FIG. 2 is a another perspective view of the molded, integral joint connecting first and second parts;

FIG. 3 is a perspective view, partially cut away, of a stationary member of the integral joint;

FIG. 4 is an exploded, perspective view of a joint formation assembly for molding the integral joint;

FIG. 5 is an exploded, perspective view of the joint formation assembly;

FIG. 6 is a perspective view of the joint formation assembly in a ready position;

FIG. 7 is a perspective view of the joint formation assembly in the ready position; and

FIG. 8 is a top view of the integral joint.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 through 3, a molded, integral joint, generally shown at 10, connects first 12 and second 14 parts such that the second part 14 is rotatable relative to the first part 12. The integral joint 10 may be formed by injection molding or injection-compression molding. In the present embodiment, the first part 12 is a semi-structural panel for a motor vehicle and the second part 14 is a vehicle door handle assembly. It is, however, appreciated that the first 12 and second 14 parts may be any of numerous structures for use in any of a variety of industries.

The integral joint 10 includes a stationary member 16 extending between opposing ends 18, 20. A first tab 22 extends between one end 18 of the stationary member 16 and the first part 12. A second tab 24 is spaced apart from the first tab 22 and extends between the opposing end 20 of the stationary member 16 and the first part 12. Thus, the first 22 and second 24 tabs connect the stationary member 16 to the first part 12. The first 22 and second 24 tabs are offset from one another along the stationary member 16. It is appreciated that the shape of the first 22 and second 24 tabs may vary.

A rotatable member or enclosure 28 extends out from one end of the second part 14. The rotatable member 28 surrounds the stationary member 16 and is free to rotate relative thereto. More specifically, the rotatable member 28 is not secured or attached to the stationary member 16 or to the first 22 and second 24 tabs. The rotatable member 28 is maintained along the stationary member 16 by the first 22 and second 24 tabs.

The particular structure, configuration, and size of the stationary 16 and rotatable 28 members may vary. In accordance with these variations, one may vary a space 29 (shown in FIG. 8) between the stationary 16 and rotatable 28 members to increase or decrease the ability of the rotatable member 28 to rotate about the stationary member 16.

A method of molding the integral joint 10 is now described with reference to FIGS. 4 through 8. The method of molding the integral joint 10 utilizes a joint formation assembly, generally shown at 30, including a plurality of slides 32, 34, 36, 38. In the present embodiment, the plurality of slides includes first 32 and second 34 central slides and first 36 and second 38 end slides. When all of the slides 32, 34, 36, 38 are moved into a ready position, as shown in FIGS. 6 and 7, moldable material is injected into the joint formation assembly 30 to form the integral joint 10.

Referring now to FIGS. 4 and 5, the first central slide 32 includes an inboard surface 40 defining an outer cavity half 42. The second central slide 34 includes an inboard surface 44 defining an outer cavity half 46. In the present embodiment, each of the outer cavity halves 42, 46 has a semi-circular shape. The second central slide 34 also includes a top surface 48 defining a passageway 50. The passageway 50 is fluidly connected to the outer cavity half 46.

When the joint formation assembly 30 is in the ready position, as shown in FIGS. 6 and 7, the first 32 and second 34 central slides are moved against one another so that the inboard surfaces 40, 44 abut one another. At this time, the outer cavity halves 42, 46 are aligned with one another to form a continuous outer cavity 52, as shown in FIG. 6. Moldable material is introduced into the passageway 50 to fill the entire outer cavity 52 and eventually form the rotatable member or enclosure 28.

Referring back to FIGS. 4 and 5, each of the first 32 and second 34 central slides also includes an inner cavity portion 54, 56 that is divorced from the respective outer cavity half 42, 46 by a separating wall 59. Each inner cavity portion 54, 56 extends between opposing ends 60, 62.

The first end slide 36 includes an inboard surface, generally indicated at 64, extending between an upper end 66 and a lower end 68. The inboard surface 64 defines an inner cavity portion 70 along the lower end 68. The inner cavity portion 70 is continuous with the inner cavity portion 56 of the second central slide 34. In addition, when the joint formation assembly 30 is in the ready position, the inner cavity portion 70 closes around the inner cavity portion 54 at the end 60 thereof. The inboard surface 64 further defines an end cavity 72 that is shaped to form the tab 22. A passageway 74 is formed in the first end slide 36 for receiving moldable material that will eventually enter the inner cavity portions 54, 56 in order to form the stationary member 16.

The inboard surface 64 of the first end slide 36 also includes end portions 76, 78 on either side of the inner cavity portion 70. When the joint formation assembly 30 is in the ready position, as shown in FIGS. 6 and 7, the end portions 76, 78 abut the top surface 48 of the second central slide 34 to seal off the outer cavity half 46 and the passageway 50. As a result, moldable material entering the outer cavity half 46 from the passageway 50 is prevented from entering the inner cavity half 70 and the end cavity 72. Thus, the outer cavity half 46 is completely divorced from the inner cavity portions 56, 70.

The second end slide 38 also includes an inboard surface 80 extending between an upper end 82 and a lower end 84. The inboard surface 80 defines an inner cavity portion 86 along the upper end 82. The inner cavity portion 86 is continuous with the inner cavity portion 54 of the first central slide 32. Together, the inner cavity portions 54, 56, 70, 86 form an inner cavity 87. When the joint formation assembly 30 is in the ready position, the inner cavity portion 86 closes around the inner cavity portion 56 at the end 60 thereof. The inboard surface 80 further defines an end cavity 88 that is shaped to form the tab 24.

The inboard surface 80 of the second end slide 38 also includes end portions 90, 92 on either side of the inner cavity portion 86. When the joint formation assembly 30 is in the ready position, as shown in FIGS. 6 and 7, the end portions 90, 92 abut a bottom surface 94 of the first central slide 32 to seal off the outer cavity half 42. As a result, moldable material entering the outer cavity half 42 is prevented from entering the inner cavity portion 86 and the end cavity 88. Thus, the outer cavity half 42 is completely divorced from the inner cavity portions 54, 86. Because the outer cavity halves 46, 42 are divorced from the respective inner cavity portions 56, 70 and 54, 86, moldable material entering the outer cavity 48 from the passageway 50 is separated from moldable material entering the inner cavity portions 54, 56, 70, 86 and the end cavities 72, 88 from the passageway 74, which in turn allows the independent formation of the rotatable member 28 along the stationary member 16. It is this independent formation of the rotatable member or enclosure 28 that allows for rotation thereof about the stationary member 16.

It is contemplated that although a particular structure for the plurality of slides 32, 34, 36, 38 has been shown and described for forming the integral joint 10, the shape, size, configuration, and number of slides may vary depending upon the specific stationary and rotatable members to be molded.

In operation, the molding of the integral joint 10 begins with the movement of the joint formation assembly 30 into the ready position, shown in FIGS. 6 and 7. Moldable material is introduced into the first end slide 36 via the passageway 74. The moldable material fills the end cavities 72, 88 and the inner cavity portions 54, 56, 70, 86, which together form the inner cavity 87. The moldable material in the inner cavity 87 and the end cavities 72, 88 forms the stationary member 16 and the tabs 22, 24, respectively. Moldable material is also introduced into the second central slide 34 via the passageway 50. The moldable material fills the outer cavity 52 to form the rotatable member 28. It is appreciated that different moldable materials may be utilized to form the stationary member 16 and the rotatable member 28. The separating wall 59 and the end portions 76, 78, 90, 92 prevent the moldable material in the outer cavity 52 from entering the inner cavity 87. Thus, the rotatable member 28 independently and separately forms around the stationary member 16, which allows rotation of the rotatable member 28 about the stationary member 16. The end result is a permanent and flexible connection between the first part 12 and the second part 14.

The particular order in which the rotatable member or enclosure 28 and the stationary structure 16 are molded may vary. More specifically, the molding of the rotatable member or enclosure 28 and the stationary member 16 can occur either simultaneously or sequentially.

The invention has been described in an illustrative manner. It is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the invention may be practiced other than as specifically described. 

1. An integrally molded joint comprising: a first part including a stationary member extending between opposing ends, said first part having a tab connecting each end of said stationary member to a remaining portion of said first part; and a second part including an enclosure formed around said stationary member and free to rotate relative thereto, said enclosure maintained along said stationary member by said tabs at each end of said stationary member.
 2. An integrally molded joint as set forth in claim 1 wherein said enclosure includes a tubular outer wall.
 3. A joint formation assembly for forming an integrally molded joint including a stationary member and an enclosure surrounding the stationary member and rotatable relative thereto, said joint formation assembly comprising: at least one central slide defining an outer cavity with opposing ends to receive moldable material for forming the enclosure, said at least one central slide also defining an inner cavity portion with opposing ends; and at least one end slide defining an inner cavity portion in fluid communication with said inner cavity portion of said at least one central slide to form an inner cavity to receive moldable material for forming the stationary member, said at least one end slide including an end portion blocking said opposing ends of said outer cavity to prevent moldable material in said outer cavity from entering said inner cavity to allow separate and independent formation of the enclosure and the stationary member with the enclosure rotatable relative to the stationary member.
 4. A joint formation assembly as set forth in claim 3 wherein said at least one central slide includes a wall located between said outer cavity and said inner cavity portion.
 5. A joint formation assembly as set forth in claim 4 wherein said at least one central slide includes a passageway in fluid communication with said outer cavity to deliver moldable material thereto.
 6. A joint formation assembly as set forth in claim 3 wherein said at least one end slide includes a passageway in fluid communication with said inner cavity portion to deliver moldable material to said inner cavity.
 7. A joint formation assembly as set forth in claim 6 wherein said at least one end slide includes an end cavity in fluid communication with said inner cavity for forming a tab connected to the stationary member.
 8. A joint formation assembly for forming an integral joint including a first part having a stationary member, and a second part having an enclosure surrounding the stationary member and rotatable relative thereto, said joint formation assembly comprising: a plurality of slides defining an inner cavity extending between opposing ends for receiving a first moldable material to form the stationary member, an outer cavity extending between opposing ends for receiving a second moldable material to form the enclosure, and blocking means for closing off said opposing ends of said outer cavity to prevent said second moldable material in said outer cavity from entering said inner cavity to ensure the separate and independent formation of the enclosure around the stationary member for rotation thereabout.
 9. A joint formation assembly as set forth in claim 8 wherein said plurality of slides includes a passageway in fluid communication with said inner cavity to deliver said first moldable material thereto.
 10. A joint formation assembly as set forth in claim 8 wherein said plurality of slides includes a passageway in fluid communication with said outer cavity at a location between said opposing ends thereof to deliver said second moldable material to said outer cavity.
 11. A joint formation assembly as set forth in claim 8 wherein at least one of said plurality of slides includes an end cavity in fluid communication with said inner cavity for forming a tab connected to the stationary member.
 12. A joint formation assembly as set forth in claim 8 wherein said first moldable material is different from said second moldable material.
 13. A joint formation assembly as set forth in claim 8 wherein said plurality of slides includes a wall positioned between said inner cavity and said outer cavity. 